Video: What is a Test Tube Used for in Science?

You've surely seen them - test tubes - but did you know that they are used for many different things across the sciences? This lesson gives you several examples of what test tubes are used for in science.

You've surely seen them - test tubes - but did you know that they are used for many different things across the sciences? This lesson gives you several examples of what test tubes are used for in science.

Handling Scientific Samples

You wouldn't stick your hands into a vat of strong acid, would you? Of course not. Neither would you want to touch dangerous bacteria. You probably wouldn't want to run experiments on your body either!

So how do people in science then ensure their safety while running all sorts of experiments and tests? Sometimes, they wear gloves. Other times, gas masks. Face shields, gowns, and many other protective measures also exist. One other way they protect themselves in science is through the use of appropriate lab equipment to handle dangerous material. One of those pieces of equipment is called a test tube.

What Is a Test Tube?

A test tube is a clear glass or plastic container that is much longer than it is wide, commonly has a U-shaped bottom, and has an open top. It's essentially a cylinder-like piece of equipment with one open end. There are many reasons for why test tubes are made out of glass or special types of plastic. That's because they possess some advantageous characteristics, such as being leak proof (so long as the tube doesn't break, of course). Compare that to a tube made out of mesh wire. That wouldn't be very leak proof, now would it?

Glass and special plastic test tubes are also non-reactive. Many metals react with all sorts of chemicals in either dangerous ways or in ways that would ruin an experiment or sample. Test tubes are also clear. It's kind of hard to see what you're doing with an experiment if the tube is made out of wood, metal, or stone, isn't it?

Test Tubes Usages in Science

Test tubes have many uses across the entire spectrum of science. Let's quickly tour a university lab facility to find out more.

First, we meet Dr. Crazy. Dr. Crazy is a chemistry professor. His last name is befitting considering all the fumes he's inhaled in his life running wild chemical experiments. Dr. Crazy explains that he uses test tubes to hold all sorts of dangerous chemicals that would otherwise burn his hands. He also uses tests tubes as containers where he mixes compounds in a safe manner. Sometimes, he heats up his experiments within a test tube using a Bunsen burner.

Dr. Crazy is a bit scary, so we move on to Dr. Culture. Dr. Culture is a biology professor who specializes in microorganisms, like fungi and bacteria. She explains that her field has a great many uses for test tubes. As just one example, she mentions that she cultures (grows) many microorganisms within test tubes by providing them a nutritious broth within the tube. Essentially, the tube serves as a home for her microorganisms.

Since we don't really want to expose ourselves to Dr. Culture's potentially dangerous bacterial cultures, let's move on to the medical part of the lab. Here we meet Dr. Ow. Dr. Ow is a physician who loves to stick people with needles in order to collect blood samples. He collects the blood into specialized test tubes. This blood is then analyzed by people and machines for various disorders.

The tubes used here, although very similar in shape to test tubes used in chemistry, are typically a bit smaller and contain specialized tops that ensure no contaminants (substances that make a sample impure) enter the tube while it is being transported, so as not to compromise the sample. They are sometimes called blood collection tubes or vacutainers instead.

Lesson Summary

So now you know: test tubes can be used for many reasons. A test tube is a clear glass or plastic container that is much longer than it is wide, commonly has a U-shaped bottom, and has an open top. Test tubes are used to hold, mix, and heat chemical experiments. They are used as homes for microorganisms when people want to culture (grow) them. They are also used as collections devices for things like blood samples.

Summary:

Earning College Credit

Did you know… We have over 160 college
courses that prepare you to earn
credit by exam that is accepted by over 1,500 colleges and universities. You can test out of the
first two years of college and save thousands off your degree. Anyone can earn
credit-by-exam regardless of age or education level.